Wrist-pin bearing



Aug. 26, 1930. M. H. ACKERMAN ,7

WRIST PIN BEAR ING .Fil ed May 2, 1928 2 Sheets-Sheet 1 6, 1930. M. H.ACKERMAN 1,

WRIST PIN BEARING I Filed May'Z, 1928 T 2 Sheets-Sheet 2 Patented Aug.26, 1930. i 1,774,219 I UN[T D-E TATES PATENTfoFF cE MICHAEL H.ACKERMAN, oFTMANsmEL D, 011:0, Assrenonor ONE-HALF To Lnwrsc.

- sIoKEL, or CALEDONIA, OHIO WRIST-PIN BEARING 1 4 Application filed May2, 1928. Serial No. 274,587.. This invention relates to wrist pinbearings taken on the line 2r-2, Figure 1, the piston of that typeemployed for connecting pistons being partly in elevation. Y ofCompressors and internal combustion Figure 3 is a section on line 3-3,Figure 2'. engines to the piston or connecting rods. 1 F gure 4 is aside elevation of the shoe Heretofore in Y structures wherein theconstituting a thrust bearing for the connect pistons are subjected .tohigh resistances, the lug r061. g

pins and bushings used for connecting the F gure 5 s a plan view oftheshoe. pistons to the rods soon become worn,"broken, Figure 6 1s atransverse section through a or distorted because allof the working'presl odified form of bearing for the connecting 0 sure andreciprocating strains aretrans nitrod of an internal combustion engine.

ted thereto ghthe piston. gure 7 a'section'on'line 77 Figure 6.

It is an object of the present invention to lgllre 8 1s atop plan viewof the bearing provide, in addition to the usual pin, a novel p 1" Shoev a form of bearing for Carrying the thrust d F1gure9 isa side elevationthereof.

reciprocating load to the crank so that the f g mi g by Characters of 65pin is relieved ofall strain and serves solely reference 1 designatesthe Piston of h as a connecting m pressor such'as used, for'jeizample,in refrig- Another object is toprovide a structure f g apparatus, thispiston being proof this character with ample bearing surfaces V 6 ith aT806582 the ends of which can be properly lubricated while" in Which arepreferably rblmdedas Shown a p ti v Tl'iisrecess is adapted to receive abearing A f th bj t i t id a d bl shoe 4 havlng rounded ends 5 andthis-shoe is tructure of this haracter the recipro adapted to be seatedagainst inner Vitll Of eating and working stresses distributed over therecess and 1 take'the Piston thrust; The

large wearing surfaces, and in which Wear Shoe 4 1188 fl sid inWhichinay be formed 7 can be compensated for by the use f {1 5 grooves6. One face of the shoe 4 is concave, hi i t d f replacing worn i d asshown at '7 and the grooves 6 open through bushings with new parts. ithis face; This concave face constitutes .a

With the foregoing and other obj ct i bearing surface for the roundedend 8 of a view which will appear as the description cqnnecting Abushing 10 is PTOVifld so proceeds th i ti id i th Co within'the endportion ofthe connecting rod bination and arrangement of parts and inthe d g through this bushing 19 El details of construction herinafter.described Wrlsh P 11116161 in Place Preferably y and claimed it beingunderstood that changes means of Set Screws 2 Which areinserted 5 iiithe precise embodiment of the invention into one end of h P and P j intoso the end portions of the'pin as shown particularly in Figure 2. I Anannular groove13 is formed in the piston adyacent theoil scraper ring 14carried herein disclosed may be .made within the scope of what isclaimed Without departing from the spirit of the invention.

In the accompanying drawings the pre- 40 ferredforms of the inventionhave been shown. i

1 0 v cumulated by the rin 14 and directed into Sald h ha V I fthegroove 13. Froiii thisgroove are ex- Flgu g t h w f tended bores'jl5which are utilized for conas qonstltuhes the Present h h, 5 ductinglubricant to opposed faces of the 9 bearlng being shown combined withthe h 4; g V V piston of the compressor of a refrlgera-ting It is to beunderstood thatthe bearing p tus, a portion of the piston being facesofthe shoe 4 and of the connecting rod shown i 1 t are concentric with thecenter of the pin 11. Figure 2 is a sectlon through the bearing As thesebearing surfaces are in contact, it

of the piston in one direction, oil will be ac by said piston so that,during the movement to which communicate with will be obvious thatduring the compression stroke of the piston the pin 11 will be relievedof excessive strain because the pressure will be transmitted'between thepiston and the connecting rod through the contacting surfaces of theshoe and theconnecting' rod.

In internal combustionengines such as Diesel engines, the structureillustrated in Figures 6 to 9 inclusive is preferably employed.Referring tothese figures it will be noted that the piston 16 isprovided, in one end, With-a recess 17 for the reception of theconnecting rod 18. The inner end of the recess 17 has an opening 19 incommunication with a recess 20in the head of the piston, this last'namcdrecess being provided for cooling and ventilation "lfll oil ports 21opening into an annular groove 22.

A shoe 23 is seated in the inner end of recess 17 ans is divided intopockets2 l all of the opening 19 and are adapted to receive lubricanttherefrom. The bottom of the shoe is concaved as shown at 25 to providea. bearing surface and oil holes open through this bearing surface fromthe respective pockets 24 as shown at 26. Air vent openings 27areprovided in opposed end walls of the shoe.

The end of the connecting rod 18 is rounded so as to fit snugly againstthebearing surface 25 of the shoe and these contacting surfaces of theshoe and connecting rod are concentric. with the longitudinal center ofa wrist pin 28 arranged diametrically within the piston. A bushing 29extends around'the pin within the end portion of the connecting rod andoil. holes 30 are formed radially within the bushing and the end portionof the connecting rod. For the purpose of retainii'ig the pin 28 inposition, an annular groove 31 formediin the piston, this groove beingextended within the one s of the pin. Seated in this groove is a ring 82which thus acts as an etiicient loci: for holding the pin againstmovement relative to the piston.

In the modified structure last described the thrust is transmittedbetween the filStOl'l and the connecting rod'through the contactingsurfaces of the shoe and rod and, therefore, the wrist pin is relievedof transverse strain and will last indefinitely. In both forms of thedevice minute adjustment of the shoe relative to the connecting rod canbe effected by inserting a shim between the shoe and the inner end ofthe recess in which-it is seated. One of these shims has beenillustrated at 33 in Figure 2 and at 34in Figure 6.

hat is claimed is: p

1. A combination with a piston having a recess extending thercinto fromone end, of a connecting rod extending into said recess, a wrist pinextending diametrically within the piston for coupling the connectingrod to the piston, a shoe seatedin the inner end of the recess andhaving a concaved bearing surface for engagement by the end of the connecting rod, the cooperating surfaces of the connecting rod and shoebeing concentric with the longitudinal axis of the wrist pin, therebeing pockets in the shoe and a recess in one'cnd portion of thepistonopening into the pockets, each pocket having an oil hole opening throughthe concaved surface of the shoe and an air vent.

2. The combination with a piston, of a connecting rod extendingthereinto and pivotally connected, a shoe seated in the piston having a.concave bearing surface for engagement by the end of the connecting rodthereby to constitute a thrust bearing for the rod, there being a pocketin the shoe and a recess in the head portio-nof the piston opening intothe pocket, and means for conducting a lubricant through the wall of thepiston head and into the recess and to the pocket, said pocket having anoil hole for directing lubricanttothe contacting faces of the shoe andconnecting rod and an air vent in the wall of the pocket.

The combination with a piston having a recess extending thereinto fromone end, of a connecting rod pivotallymounted in the cess, ashoe seatedin the recess and constituting a thrust bearing for the connecting rod,said shoe having a pocket provided with a lubricant outlet and anairvent, said outlet constituting means for directing a lubricantontothe cooperating faces of the connecting rod and the shoe and saidair vent opening into the recess containing the connecting rod, andmeans for directing a lubricant through the wall of the piston into thepocket.

In testimony that I claim the foregoing as my own, I have heretoaflizied my signature.

MICHAEL H. ACKERMAN.

